• The Journal of Korean Society for Radiation Therapy
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• v.29 no.2
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• pp.53-64
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• 2017

Purpose: To evaluate the usefulness of the $HexaPOD^{TM}$ evo RT system(6DoF couch) and the tendency of dose difference according to size of rotational direction error for volumetric rotational modulated radiotherapy(V-MAT) in patients with long target lengths. Therefore, it is suggested to recommend the need for rotational error correction. Materials and Methods: Ten patients with Esophagus cancer or Breast cancer including SCL treated with HexaPOD 6DoF(Six-Degree of Freedom) couch were included in this study. 6DoF couch was used to measure the difference in dose according to the rotation error in the directions of Rx(pitch), Ry(roll), and Rz(yaw). Each rotation error was applied. Positioning variation on x, y and z axis was verified and random variations were made by 6DoF couch with positioning variation. Modified DQA is conducted and point dose and gamma value are analyzed and compared. In addition, after applying the rotation error every $1^{\circ}$ to treatment plans of each target with a diameter of 3 cm, 5, 10, 15, and 20 cm respectively, gamma passing rate is being monitored by its aspect of change according to types and sizes of the target length and rotation error. Results: Mean error of the point dose and Gamma passing rate when the position variation was applied were $2.50{\pm}1.11%$ and $84.1{\pm}7.39%$ in the Rx direction, $2.36{\pm}1.16%$, and $81.0{\pm}8.49%$ in the Ry, $2.35{\pm}1.10%$ and $84.4{\pm}6.99%$ in the Rz direction, respectively. As a result of analysis on gamma passing rate according to types and sizes of the target length and rotation error, the gamma passing rate tended to decrease with increasing rotation error in the Rx and Rz directions except Ry direction. In particular, the lowest gamma passing rate (74.2 %) was in the case of $2.5^{\circ}$ rotation error in Rz direction of the target of 10 cm. Conclusion: The correction of the rotational error is needed for volumetric modulated radiotherapy of the treatment area with a long target length, and the use of 6DoF couch will improve the reproducibility of the patient position and the quality of the treatment.

• Korean Journal of Organic Agriculture
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• v.23 no.1
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• pp.113-121
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• 2015

This study was conducted to evaluate the effect of crop rotation cultivation on the suppression of garlic white rot caused by Sclerotium cepivorum in the mini plot ($2^*1^*$ 0.5 m). Six crops, soybean, sesame, mung bean, squash, crotalaria and spring onion, were previously transplanted in the mini-plots infested with S. cepivorum before garlics were planted. After cultivation of the previous crops, garlic was sown in the mini-plot. Non-cultivation plots and non-infested plots with white rot pathogen were used as control. The effect of crop rotation cultivation on the suppression of garlic white rot was evaluated by investigating comparatively the disease incidence (the percentage of infected plants) and yields. As a results, infection rate of garlic white rot was recorded lower in the non-infested plot, crotalaria and soybean cultivation than in the plot of the other crop cultivation. Especially when squash was previously cultivated and garlics were planted in 2013, infection rate of garlic white was recorded the highest score. In 2014, the infection rate of garlic white were low in the garlic on soybean, crotalaria and spring onion treatment whereas it was high in squash treatment, as well. In 2013, garlic yield was the highest in no inoculation plot, followed by crotalaria, soybean, no crop cultivation, sesami, mungbean, squash cultivation plot. In 2014, the yield in the plot of crotalaria and soybean was much higher than that in no inoculation plot. Based on above-described results, it is considered that soybean-garlic and crotalaria-garlic cultivation system can be good crop rotation systems to control garlic white rot.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.1 s.256
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• pp.83-90
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• 2007

The present study investigated the effects of channel rotation and bleed flow on heat/mass transfer in a $90^{\circ}$ ribbed square channel. The bleed holes were located between the rib turbulators on the leading surface and those on the trailing surface case by case. The tests were conducted under the conditions of various bleeding ratios (0.0, 0.2, 0.4) and rotation numbers (0.0, 0.2, 0.4) at Re=10,000. The results suggested that heat/mass transfer characteristics were influenced by the Coriolis force, bleed flow and bleed hole location. The heat/mass transfer on the surface with bleed flow was more increased than that without bleed flow but that on the opposition surface was decreased. Those were due to the effects of the tripping flow and the diminution of main flow rate respectively. The results also showed that the heat/mass transfer characteristics were different according to bleed hole location and channel rotation.

• Structural Engineering and Mechanics
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• v.58 no.1
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• pp.181-197
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• 2016

In this paper, we investigated the propagation of surface waves in a nonhomogeneous rotating fibre-reinforced viscoelastic anisotropic media of higher order of nth order including time rate of strain. The general surface wave speed is derived to study the effect of rotation on surface waves. Particular cases for Stoneley, Love and Rayleigh waves are discussed. The results obtained in this investigation are more general in the sense that some earlier published results are obtained from our result as special cases. Also results for homogeneous media can be deduced from this investigation. For order zero our results are well agreed to fibre-reinforced materials. Also by neglecting the reinforced elastic parameters, the results reduce to well known isotropic medium. It is also observed that, surface waves cannot propagate in a fast rotating medium. Comparison was made with the results obtained in the presence and absence of rotation and parameters for fibre-reinforced of the material medium Numerical results are given and illustrated graphically. The results indicate that the effect of rotation and parameters for fibre-reinforced of the material are very pronounced.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.346-354
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• 2001

This study was conducted to investigate the status and problems, and suggest the proper improvement of provincial rotation hunting system in Korea. There were many problems in recently provincial rotation hunting system, such as, difficulty of budget interiority, low participation rate of hunters, low specialization degree of officers on their job, and extremity of illegal capture of wildlife by the absence of wildlife manager. The municipal hunting system, which have many merits, such as, increase of hunters' participation and income of municipality, creation of engagement, and prohibit of illegal capture of wildlife would be suggest for the improvement of hunting system.

• The KIPS Transactions:PartB
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• v.9B no.4
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• pp.509-516
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• 2002

This paper proposes an efficient algorithm which recognizes the mixed document image consisting of the images, texts, tables, and straight lines. This system is composed of three steps. The first step is the detection of rotation angle for complementing skewed images, the second is detection of erasing an unnecessary background region and last is the classification of each component included in document images. This algorithm performs preprocessing of detecting rotation angles and correcting documents based on the detected rotation angles in order to minimize the error rate by skewness of the documentation. We detected the rotation angie using only horizontal and vertical components in document images and minimized calculation time by erasing unnecessary background region in the detecting process of component of document. In the next step, we classify various components such as image, text, table and line area included in document images. we applied this method to various document images in order to evaluate the performance of document recognition system and show the successful experimental results.

• Korean Journal of Applied Biomechanics
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• v.26 no.4
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• pp.369-375
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• 2016

Objective: The purpose of this study was to investigate the possibility of injuries and the types of movement related to damage by body parts, and to prepare for prevention of injuries and development of a training program. Method: For this study, the experiment was conducted according to levels of 60 percentages (ST) and 85 percentages (MA) and 10 subjects from the Korean elite national weightlifting team were included. Furthermore, we analyzed joint moment and muscle activation pattern with three-dimensional video analysis. Ground reaction force and EMG analyses were performed to measure the factors related to injuries and motion. Results: Knee reinjuries such as anterior cruciate ligament damage caused by deterioration of the control ability for the forward movement function of the tibia based on the movement of the biceps femoris when the rectus femoris is activated with the powerful last-pull movement. In particular, athletes with previous or current injuries should perceive a careful contiguity of the ratio of the biceps femoris to the rectus femoris. This shows that athletes can exert five times greater force than the injury threshold in contrast to the inversion moment of the ankle, which is actively performed for a powerful last pull motion and is positively considered in terms of intentional motion. It is activated by excessive adduction and internal rotation moment to avoid excessive abduction and external rotation of the knee at lockout motion. It is an injury risk to muscles and ligaments, causing large adduction moment and internal rotation moment at the knee. Adduction moment in the elbow joint increased to higher than the injury threshold at ST (60% level) in the lockout phase. Hence, all athletes are indicated to be at a high risk of injury of the elbow adductor muscle. Lockout motion is similar to the "high five" posture, and repetitive training in this motion increases the likelihood of injuries because of occurrence of strong internal rotation and adduction of the shoulder. Training volume of lockout motion has to be considered when developing a training program. Conclusion: The important factors related to injury at snatch include B/R rate, muscles to activate the adduction moment and internal rotation moment at the elbow joint in the lockout phase, and muscles to activate the internal rotation moment at the shoulder joint in the lockout phase.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2207-2220
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• 2021

Lead alloy is used as coolant in Lead-based cooled Fast Reactor (LFR). The natural characteristics of lead alloy are combined with the simple structural design of LFR. This constitutes the inherent safety characteristics of LFR. The main work of this paper is to take the main coolant pump (MCP) in the lead-cooled fast reactor (LFR) as the research object, and to study the flow pattern distribution of the internal flow field under the reverse rotation pump condition, the reverse rotation positive-flow braking condition and the reverse rotation negative-flow braking condition. In this paper, the double-outlet volute type and the space guide vane are selected as the potential designs of the CLEAR-I MCP. In this paper, the CFD method is used to study the potential reverse accident of the MCP. It is found that the highest flow velocity in the impeller appears at the impeller outlet, and the Q-H curves of the two design programs basically coincide. The space guide vane type MCP has better hydraulic performance under the reverse rotation positive-flow condition, the Q-H curves of the two designs gradually separate with increasing flow rate, and the maximum flow velocity inside the space guide vane type MCP is obviously lower than that of the double-outlet volute type. For the reverse rotation test of MCP, only the condition of the forward rotating pump of the main coolant pump is tested and verified. For the simulation of the MCP in LBE medium, it proved that the turbulence model and basic settings selected in the simulation are reliable.

• Journal of The Korean Association of Information Education
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• v.1 no.1
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• pp.28-37
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• 1997

This paper presents a new neural network based on fuzzy set and its application to invariant character recognition. The fuzzy neural network consists of five layers. The results of simulation show that the network can recognize characters in the case of distortion, translation, rotation and different sizes of handwritten characters and even with noise(8${\sim}$30%)). Translation, distortion, different sizes and noise are achieved by layer L2 and rotation invariant by layer L5. The network can recognize 108 examples of training with 100% recognition rate when they are shifted in eight directions by 1 pixel and 2 pixels. Also, the network can recognize all the distorted characters with 100% recognition rate. The simulations show that the test patterns cover a ${\pm}20^{\circ}$ range of rotation correctly. The proposed network can also recall correctly all the learned characters with 100% recognition rate. The proposed network is simple and its learning and recall speeds are very fast. This network also works for the segmentation and recognition of handwritten characters.

• Journal of Veterinary Clinics
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• v.35 no.5
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• pp.200-205
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• 2018

This retrospective study is designed to compare the clinical results of tibial tuberosity transposition (TTT) and anti-rotation suture (ARS) treatments for medial patellar luxation (MPL). Medical records of 133 dogs were reviewed that had undergone surgical correction of MPL between January 2013 and May 2017. MPL correction was performed on 182 stifles, with TTT and ARS being performed on 101 stifles and 81 stifles. The common dog breeds receiving surgical treatment for MPL were Maltese, Pomeranian, Chihuahua and Poodle. Mean age of dogs with MPL was 32.6 months, and their mean body weight was 4.26 kg. Seventy dogs (52.6%) were male and 63 (47.4%) were female. Of the 182 stifles with MPL, grade II, III and IV were 18.7%, 72.0% and 9.3%. Total complications after TTT and ARS were recorded in 16.8% and 29.6%. Major complications after TTT and ARS were recorded in 5.9% and 12.3%, minor complications after TTT and ARS were recorded in 10.9% and 17.3%. The risk of complication and reluxation rate after TTT were significantly lower than that for ARS (p < 0.05). However, the rate of reluxation among dogs treated by ARS (1.2%) for grade II MPL was significantly lower than that for dogs treated by ARS (8.6%) for grade III MPL (p < 0.05). The TTT group had a shorter recovery period after surgical intervention than that in the ARS group (p < 0.001). In conclusion, TTT had a significantly lower incidence of complication and a shorter recovery period than ARS. However, ARS for grade II MPL appears to be a good surgical option for reducing the rate of reluxation after surgery. These results of this study could be used to provide therapeutic guidelines for surgical MPL correction in small-breed dogs.